Rock

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   \_ (     :   __/
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Rocks and stones are natural formations of minerals. They are the most common tools in simple technology alongside wood for their universality, availability, variety of shape, size, and weight. They have a wide variety of uses:

A basic axe can be made out of a rock, by sharpening it with a sturdier one or a crystal/mineral (ex. shaping basalt with a piece of quartz).